most prob know already but there is a trick of tagging him and then dropping raid to form another to get more then 40 people a chance at the loot so there shouldn't really be any competition for the kill (at least from alliance).
most recent recorded kills -
12/25 - early morning
12/22 around 2:15pm server
12/15/12 - 5am
12/9/12 - around 8pm server
12/4/12 - Killed around 2am server.
11/23/12 - 640pm server time
if u were there for any galleon kills more recent plz share.